Xp. Hu et al., COMPARISON OF T-2(ASTERISK)-WEIGHTED SEQUENCES FOR FUNCTIONAL MRI, International journal of imaging systems and technology, 6(2-3), 1995, pp. 184
Several sequences, including conventional gradient-echo sequence (e.g.
, FLASH), gradient-echo echo-planar imaging (EPI), T-2 prepared ultra
fast gradient echo technique (TurboFLASH), and T-2-weighted spiral se
quence, are currently used for T-2-weighted functional magnetic reson
ance imaging. This paper presents a comparison of FLASH, gradient-echo
EPI, and T-2-prepared TurboFLASH. Experimental results have demonstr
ated that these sequences have different susceptibility to physiologic
fluctuation, which is likely the dominant source of noise. EPI images
exhibit the lowest relative fluctuation, while images obtained by FLA
SH and TurboFLASH, respectively, display similar relative fluctuation.
Functional maps generated using these sequences are comparable but ex
hibit different sensitivity to activation from large vessels. Conseque
ntly, interpretation of activation results from various maps should ta
ke into account the difference in the sequences. (C) 1995 John Wiley &
Sons, Inc.